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AK4112B Datasheet, PDF (15/30 Pages) Asahi Kasei Microsystems – HIGH FEATURE 96kHz 24BIT DIR | |||
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ASAHI KASEI
[AK4112B]
 Error Handling
There are the following five factors which ERF pin goes âHâ. ERF pin shows the status of the internal PLL operation and
it is âLâ when the PLL is OFF (Clock Operation Mode 1).
1. Unlock Error
2. Parity Error
3. Biphase Error
4. Frame length Error
5. STC (Status Change) flag=â1â
: âHâ when the PLL goes UNLOCK state.
: Updated every sub-frame cycle.
: Updated every sub-frame cycle
: Updated every sub-frame cycle
: Holds â1â until reading 03H.
In Parallel Mode, ERF pin outputs the ORed signal including the factors of 1,2,3 and 4. Once ERF pin goes âHâ, it
maintains âHâ for 1024/fs cycles after the all error factors are removed. Table 11 shows the state of each output pins
when the ERF pin is âHâ. The Frame length Error is occurred when the interval of preamble in biphase signal is incorrect.
When unlock state, the channel status bits are not updated and the previous data is maintained.
Error
Unlock Error
Parity Error
Biphase Error
Frame Length Error
AUTO
âLâ
Output
Output
Output
SDTO
âLâ
Previous Data
Previous Data
Previous Data
V
âLâ
Output
Output
Output
Table 11. Error handling (Parallel Mode)
In Serial Mode, ERF pin outputs the ORed signal including the factors of 1,2,3,4 and 5. However, Parity, Biphase and
Frame Length Error can be masked by MPAR bit, and the STC flag can be masked by MSTC bit. When those are masked
by each bit, the error factor does not affect ERF pin operation. The STC flag is set whenever a comparison between the
last sample of bits D5-0 of the receiver status 1 register (03H) and the new sample are different This comparison is made
every fs cycle. The STC flag is reset by reading the register 03H. This flag is also disabled during the first block after
reset.
Once ERF pin goes âHâ, it maintains âHâ for 1024/fs cycles (can be changed by ERFH0-1 bits) after the all error factors
(In case of STC, from STC flag â1â to reading 03H) are removed. Once PAR, BIP, FRERR, V or UNLOCK bit goes â1â,
it returns â0â by reading Receiver Status 2 (04H). When unlock state, the channel status bits are not updated and the
previous data is maintained.
Error
Register
& Status
UNLOCK PAR BIP FRERR STC
Unlock Error
1
0
0
0
0
Parity Error
0
1
0
0
0
Biphase Error
0
0
1
0
0
Frame Length Error
0
0
0
1
0
Status change
0
0
0
0
1
AUTO
âLâ
Output
Output
Output
Output
Pin
SDTO
âLâ
Previous Data
Previous Data
Previous Data
Output
V
âLâ
Output
Output
Output
Output
TX
Output
Output
Output
Output
Output
Table 12. Error handling (Serial Mode; MPAR=1, MSTC=1)
MS0078-E-02
- 15 -
2004/04
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